The SW page is not correct in content or placement. The 2 5/8 gauges were
oil and water temp,
oil and FUEL pressure and an AMP meter
Fuel pressure is of no value, but a fuel gauge is critical for street. A volt gauge is safer than an AMP gauge and more useful. These units were all mechanical meaning they had long one piece capillary tubes. A pain to install and remove.
A better solution is the stuff from Kirkham. Right size and 270' sweep, but all modern electrics.
http://www.thomaskirkham.com/289gauges.html